440Hz (Hz=Hertz the unit of frequency) is the A above middle C (the usually "tuning note" for orchestras) and the Bb above is therefore approximately 466Hz. As today's standard scale has an equal temperament ie 12 increments on a logarithmic scale doubling every octave- see http://en.wikipedia.org/wiki/Equal_temperament
The lowest open note on Bb Trumpet/cornet is an octave below ie approximately 233Hz.
The lowest open note on Bb Euphonium is a further octave below ie approximately 116Hz.
And the lowest open note on BBb Bass is a further octave below ie approximately 58Hz. I've avoided pedal notes which are a further octave lower and approximately 29Hz on a BBb Bass. In principle, a very good player could descend a further half octave using the standard valves ie down to approximately 20.5Hz. Other tubas can't play this low eg a EEb tuba is a 4th higher ie frequencies are higher by a factor of 1.3348.
Re: Extremely low notes 14:25 on Saturday, January 5, 2008
theres a instrument called a tubax, its a sub contrabass saxaphone 8 feet hight with 28 feet of tubing. it can play the space below the 8th leger line and can be tuned to play too low for humans to hear